[CISCN2019 North Division Day1 Web5] CyberPunk

Brush title record: [CISCN2019 North Division Day1 Web5] CyberPunk

Recurring topic links: https://buuoj.cn/challenges
Reference Links: ciscn2019 North Division semifinal day1web5CyberPunk

First, knowledge

1, pseudo-protocol file read

file=php://filter/convert.base64-encode/resource=index.php

2, error injection

confirm.php no injection point, can be injected into the address database, although there is addslashesan escape, but the modified address can be found will be preserved, so that the second revision when you can trigger an error